Are you talking about the sorta whitish stuff? I think I may see it in the upper right hand of the water dish. If so, I believe you are seeing urates. Urates are normal, much more so in some species it seems then others. You just want them to stay sorta like ummmm very watery creamy toothpaste might be a good thing to use as reference. You don't want them to get really gritty.
Here is a thread about it:
I need to come up with something that is a really good common to everybody type of visual reference, any body have any good suggestions as to what to compare urates to?
I need to come up with something that is a really good common to everybody type of visual reference, any body have any good suggestions as to what to compare urates to?